Dissecting the role of the nuclear basket in regulating mRNA metabolism

调节其基因的表达是任何生物体的基本任务。在真核细胞中，储存遗传信息的部位（细胞核）和将信息翻译成蛋白质的部位（细胞质）被双层胆脂膜隔开，大分子不能透过。在细胞核中，DNA储存的细胞器中，遗传信息首先被复制到一种称为mRNA的信使分子中，mRNA必须离开细胞核到达细胞质才能翻译成蛋白质。到达蛋白质合成位点的唯一途径是通过核孔复合物（NPC），一种嵌入核膜中的大分子复合物。我们研究计划的长期目标是了解与mRNA结合的不同因子和组成NPC的因子之间的相互作用如何控制mRNA从细胞核到细胞质的有效和选择性出口。为了进一步深入了解这一重要过程，我们将使用不同的生物物理，生物化学和遗传工具。首先，我们将使用最近开发的超分辨率显微镜技术，允许在真实的时间和纳米分辨率下跟踪单个mRNA分子，以确定核篮（mRNA到达核外围时遇到的第一个结构）如何调节mRNP进入NPC。此外，使用基因组和蛋白质组学分析，我们将研究细胞如何诱导NPC组成的变化，以改变细胞暴露于压力时的基因表达程序。通过完成这个项目，我们将揭示这一基本细胞过程的重要机制细节，并建立相关的生物物理工具，以研究单分子分辨率的不同细胞过程。

Regulating the expression of its genes is an essential task for any living organism. In eukaryotic cells, the site where the genetic information is stored, the nucleus, and the site where the information is translated into protein, the cytoplasm, is separated by a double bilipidic membrane, impermeable to large molecules. In the nucleus, the organelle where DNA is stored, the genetic information is first copied into a messenger molecule, called mRNA, which has to exit the nucleus and reach the cytoplasm to get translated into proteins. The only path to reach the site of protein synthesis is through the nuclear pore complex (NPC), a large macromolecular complex embedded in the nuclear membrane. The long-term objective of our research program is to understand how the interplay between different factors that bind to the mRNA and factors composing the NPC control efficient and selective export of mRNAs from the nucleus to the cytoplasm. To gain further insight into this essential process, we will use different biophysical, biochemical and genetic tools. First, we will use recently developed super resolution microscopy techniques that allow to follow individual mRNA molecules in real time and in nanometer resolution to determine how nuclear basket, the first structure mRNAs encounter when reaching the nuclear periphery, regulates the access of mRNPs to the NPC. Furthermore, using genomic and proteomic assays, we will investigate how cells induce changes in the composition of the NPC to change gene expression programs when cells are exposed to stress. By completing this project we will reveal important mechanistic details that underlie this essential cellular process and establish biophysical tools relevant to study different cellular processes in single molecule resolution.